Special scientific report

321

HERRING SPAWNING SURVEYS

IN SOUTHEASTERN ALASKA

Marine Biological Laboratory

"L I BR .A. R. "ST

WOODS HOLE, MASS,

SPECIAL SCIENTIFIC REPORT- FISHERIES No. 321

UNITED STATES DEPARTMENT OF THE INTERIOR
FISH AND WILDLIFE SERVICE

EXPLANATORY NOTE

The series embodies results of investigations, usually of restricted
scope, intended to aid or direct management or utilization practices and as
guides for administrative or legislative action. It is issued in limited quantities
for Official use of Federal, State or cooperating agencies and in processed form
for economy and to avoid delay in publication .

United States Department of the Interior, Fred A. Seaton, Secretary
Fish and Wildlife Service, Arnie J. Suomela, Commissioner

HERRING SPAWNING SURVEYS IN SOUTHEASTERN ALASKA

by

Bernard Einar Skud

Fishery Research Biologist

Bureau of Commercial Fisheries

United States Fish and Wildlife Service
Special Scientific Report — Fisheries No. 321

Washington, D. C.
December 1959

CONTENTS

Page

Introduction 1

Methods of aerial survey 2

Spawning localities

Time of spawning 4

Characteristics of spawning beaches 4

Summary 4

Literature cited 16

li

Figure 1. — Aerial views of herring milt clouds at Fish Egg Island
near Craig, Alaska.

111

HERRING SPAWNING SURVEYS IN SOUTHEASTERN ALASKA

by

Bernard Einar Skud
U. S. Fish and Wildlife Service
Galveston, Texas

ABSTRACT

Aerial surveys to observe milt
herring in Southeastern Alaska waters ho
assessing the extent of spawn deposition
altitudes of 500 to 700 feet and at crui
mileage of beach utilized for spawning i
of navigation charts. The surveys have
80 previously unreported spawning beache
preliminary flights have also added valu
of spawning and the physical characteris

clouds produced by spawning
Id promise as a method for

Flights are conducted at
sing speeds of 120 knots. The
s recorded on reduced prints
resulted in the discovery of
s. Observations during these
able information on the time
tics of the beaches.

INTRODUCTION

Biological studies of Pacific herring,
Clupea harengus pallasi, in Alaska have
provided valuable information regarding the
life history and behavior of this species
(Rounsefell, 1930), but violent fluctua-
tions in catches have not been adequately
explained. Catch statistics suggest that
changes in abundance are responsible for
the fluctuations, but other evidence sug-
gests that availability of herring to the
fishing gear may vary considerably.

To resolve this difference, abundance
estimates based on other than catch-effort
data were considered. Canadian biologists
had developed one such method by appraising
egg deposition at time of spawning. Ground
surveys measuring egg density and length
and width of areas utilized for spawning
afford a measure of total mileage of deposi-
tion, which is used as a comparative index
of abundance (Taylor, 1955). In Southeast-
ern Alaska spawning areas are so widespread
that intensive ground surveys to assess
spawn deposition are not feasible. There-
fore, a method of aerial assessment was
developed through the collaboration of L. N.

Kolloen 1/ f G. W. Hilsinger, and C. H.
Elling of the Bureau of Commercial Fisher-
ies, and J. C. Stevenson of the Fisheries
Research Board of Canada. In the spring of
1953 a systematic aerial survey was made in
British Columbia and Southeastern Alaska.
The success of this initial survey encour-
aged further investigation, and somewhat
more refined surveys have continued in
Southeastern Alaska.

The prime objective of aerial surveys
is to determine the mileage of beach used
for spawning in a given area. The extent
of spawn deposition is assumed to indicate
size of spawning population. In addition
to comparison of annual changes in actual
mileage utilized, changes in areas used for
spawning can be studied and may help to
determine environmental requirements for

1/ The author especially wishes to acknowl-
edge the late L. N. Kolloen who initi-
ated this research and who unfortunately
died in a plane crash while on official
business in Southeastern Alaska on Sep-
tember 1, 1954.

spawning. Aerial surveys also afford a
means of studying timing of spawning activ-
it ies.

The purpose of this report is (1) to
describe the procedures of the aerial survey
and (2) to record preliminary information
gained from surveys of the past three years.

METHODS OF AERIAL SURVEY

The Pacific herring spawns in inter-
tidal areas, and during spawning activity
clouds of milt appear in the water along
the shoreline. These milt clouds may be
readily observed from the air (fig. 1); they
have been spotted from as high as 6,500
feet, and are most certainly visible from
greater heights. Most aerial surveys are
conducted at altitudes between 500 and 700
feet. In clear weather, milt clouds have
been seen at three miles from these heights.
The exact coloration of the milt varies
with lighting conditions. During bright,
cloudless days the milt appears milky white,
but during overcast periods it may vary
from pale yellow to yellowish green. The
density of the milt also produces variations
in color.

The rate at which milt disperses and
is no longer visible depends on tidal
action, wind, and density of deposition.
The schooling behavior of Pacific herring
is such that spawning is usually intense
and continuous, and dispersion of milt from
an area is rarely completed in a day's time.
After the milt has disappeared, the beach
utilized for spawning may be detected by
the presence of sea gulls actively feeding
on eggs. Gulls line the spawning beach in
countless thousands and distinctly outline
the areas of egg deposition. Observations
are classified as (1) active spawn when
milt is visible and (2) old spawn when
gulls are the only evidence of spawning.

Aerial surveys require an observer
familiar with the territory and character-
istics of spawning beaches. Aircraft used
thus far for surveys (Grumman Goose and
Super Widgeon) cruise at speeds of 120
knots, and though a trained observer would
have little difficulty locating specific
landmarks, the novice might easily be con-
fused. When necessary, two or three passes
are made over the same grounds to ensure
accurate mileage determinations. During

flight the observer plots the entire route
of the survey on reduced prints of naviga-
tion charts and marks beach areas used for
spawning. After each flight the observer
measures the spawning beach marked on the
chart and determines the mileage observed.

Time of spawning varies in each area,
and to provide coverage of all major spawn-
ing areas, surveys are made from mid-March
to mid-May. Spawning in any location may
continue for as long as five weeks and re-
peated flights are necessary to adequately
assess egg deposition. Results of all
flights in a given area are compiled on a
single master chart. This provides a compo-
site picture of the spawning beach utilized
during the season. The 1955 master chart
of one of the major spawning areas is pre-
sented in figure 2.

Attempts to standardize survey methods
have met with several obstacles of which
weather conditions are most important and
govern the days selected for survey either
because flying is impossible, or visibility
is so poor that surveys are not practical.
Yearly variations in time of spawning pos-
sible negate the necessity of flying on a
given day. Rather, coverage or number of
days and hours flown would appear to be of
greater importance, so that standardization
of flying time would provide a useful com-
parative index, whereas surveys on given
days could well distort such an index.

Availability of aircraft has also been
a factor in standardizing methods. Avail-
able flight time has limited the extent
of surveys, which of necessity have been
centered in areas of concentrated spawning
activity. Thorough and complete coverage
has been attained in these area, but in
areas of very light spawning there has been
no standardized coverage.

The goal of future survey work is to
develop a standardized method of survey from
which the size of spawning populations can
be estimated. Route and area of coverage,
time lapse between flights, and numbers of
surveys per area have yet to be established.

SPAWNING LOCALITIES

Rounsefell (1930) lists the reported
spawning areas of herring from California
to the Bering Sea. Aerial surveys have

Figure 2. — Master chart of a major spawning area.

substantiated many areas in Rounsef ell's
listing for Southeastern Alaska and also
have located additional spawning areas.
Aerial surveys also have shown that areas
utilized for spawning may differ from year
to year. Some areas listed by Rounsefell
have not been utilized in recent years.
Tables 1 to 5 and figures 3 to 8 list spawn-
ing areas in Southeastern Alaska discovered
by the aerial survey method and compare
them with Rounsefell's listing.

The points listed represent definitive
landmarks nearest actual spawning beaches
and carry no significance as to extent of
spawning. Some locations encompass far more
ground than was utilized for spawning and
others only a fraction of the total spawning
area. For example, Pybus Bay (No. 16 on
fig. 6) spawning includes but a very small
portion of the bay; on the other hand,
spawning at Fish Egg Island (No. 14 on fig.
5) occurs around the entire island. Spawn-
ing has been observed by air on 20 of the 57
spawning beaches listed by Rounsefell, and
82 new beaches have been located since 1953.
Extensive aerial surveys, rather than an
increase in beaches actually used for spawn-
ing, probably explain the large number of
new spawnings discovered. There are three
possible explanations why the 37 beaches
listed by Rounsefell were not detected by
aerial survey: (1) Changes may have taken
place in spawning locales since 1930; (2)
timing of aerial surveys may not have been
synchronized with time of spawning in some
areas; and (3) spawning beaches included
those reported by local residents.

TIME OF SPAWNING

Rounsefell (1930) described a north-
erly and westerly progression in spawning
time along the Pacific coast from Califor-
nia to the Bering Sea. Although some
spawning areas in Southeastern Alaska follow
this same progression, other areas do not.
The earliest spawning occurs in the Craig
area during the last two weeks of March,
followed by the Kah Shakes and Sitka areas
in late March and early April, and the Auke
Bay area in late April and early May. The
Behm Canal, Etolin Island, and areas in the
vicinity of Frederick Sound are somewhat
erratic in time of spawning. Spawning has
been reported in early April and in June.
At present no explanation for variance in
spawning progression is apparent. Differ-
ences in environmental requirements of
different races could, of course, influence
time of spawning.

CHARACTERISTICS OF SPAWNING BEACHES

In conjunction with aerial surveys,
a few ground surveys have been undertaken.
Considerable variation of physical charac-
teristics exists among the beaches examined.
Spawning beaches at Fish Egg Island (fig.
5) are for the most part, gently sloping
gravel beaches with patches of eelgrass
(Zostera) , rockweed (Fucus ) , and vine kelp
(Macrocystis) . In contrast, spawning
beaches in Pearl Harbor (fig. 7) are steep,
rocky shores covered with rockweed in the
intertidal zone and beds of bladder kelp
(Nereocystis) in deeper water. Eggs were
attached to all vegetation but predominant-
ly to eelgrass and rockweed. Unidentified
vegetation was utilized to a much lesser
degree.

In some areas the same spawning
beaches are utilized annually, whereas in
others there is a definite change in loca-
tion of spawning beaches from year to year.
Observations during the past three years
indicate that time of spawning varies less
in areas where the same beaches are utilized
year after year. For example, the first
spawning of the Craig population in 1953 was
reported on March 23, in 1954 on March 23,
and in 1955 on March 28. This initial spawn-
ing was always on the west shore of Fish Egg
Island. In the Behm Canal area, on the
other hand, the first spawning was reported
on April 6 at Helm Bay in 1953, on April 26
at Indian Point in 1954, and on April 19 at
Caamano Point in 1955.

SUMMARY

A method of aerial survey, pioneered
by L. N. Kolloen, has been developed to
observe spawning activities of herring in
Alaska. Surveys are conducted at altitudes
of 500 to 700 feet. Reduced prints of
navigation charts are used to plot survey
routes and locations of beach areas used
for spawning. Observations of spawning are
recorded as "active spawn" when milt is
present and "old spawn" when the only evi-
dence of spawn is birds in the area.

A comparison of Southeastern Alaska
spawning beaches located by air and those

SOUTHEASTERN ALASKA

C. E<Jg«cumb«J-

Biorko H

CAPE OMMANEY

20 miles

DIXON ENTR AN C E

Figure 3. — Map of Southeastern Alaska showing the six main spawning areas
(circled) and the boundaries of subsequent figures used to lo-
cate specific spawning beaches.

Figure 4. — Chart of spawning beaches in the vicinity of Ketchikan.

Table 1. --Spawning beaches in the vicinity of Ketchikan

(x = spawning observed; o = no spawning observed;
- = not surveyed)

Aerial survey

Number

Locality

Rounsefell

1953

1954

1955

1

Foggy Bay

X

X

X

2

Kirk Point

X

X

X

3

Kah Shakes Cove

o

X

X

4

Kah Shakes Point

o

o

X

5

Annette Point

o

X

o

6

Ham Island

o

X

X

7

Mountain Point

o

X

o

8

George Inlet

-

X

o

9

Clover Pass

X

X

o

10

Loring

X

o

o

o

11

Indian Point

o

X

o

12

Spacious Bay

X

o

o

o

13

Port Steward
Morgan's Cove-

X

o

o

o

14

X

15

Point Francis

X

X

X

16

Raymond Cove

X

X

X

17

Wadding Cove

o

X

o

18

Trunk Island

X

o

X

o

19

Helm Bay

X

X

o

20

Smuggler's Cove

o

X

o

21

Bond Bay

X

o

X

22

Caamano Point

X

o

o

X

23

Kasaan Village

X

o

o

24

Sandy Point

o

o

X

25

Karta Bay

X

o

o

26

Tolstoi Bay

X

o

o

27

N. E. of Ship Island

o

o

X

28

Meyer's Chuck

X

o

o

o

29

Lemesurier Point

X

X

X

30

Union Bay

X

o

o

o

31

Vixen Inlet

X

o

o

o

32

Stones Island

X

o

o

33

Etolin Island

X

o

X

34

Kelp Point

o

-

X

35

Stanhope Island

o

-

X

36

Marble Point

o

-

X

37

Burnett Inlet

o

-

X

1 / Local name, exact location unknown.

Figure 5. — Chart of spawning beaches in the vicinity of Craig.

Table 2. --Spawning beaches in the vicinity of Craig

(x = spawning observed; o = no spawning observed;
- = not surveyed)

Aerial survey
Number Locality Rounsefell 1953 1954 1955

1

2

3

4

5

6

7

8

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25

Rose Inlet

X

o

-

-

Goat Island

o

-

X

Trocadero Bay

X

o

o

o

Suemez Island

X

o

o

Baker Island

X

o

o

Coronados Islands

o

o

X

Port Bagial

X

o

X

Cape Suspiro

X

X

X

Bellana Islands

X

o

o

Craig small boat harbor

X

X

X

Crab Bay

X

X

X

Craig

X

o

o

o

Fish Egg Island

X

X

X

X

Klawock Reef

X

o

X

Clam Island

X

X

o

X

Wadleigh Island

X

X

X

Klawock Inlet

o

X

X

Alberto Islands

o

X

X

Abbess Island

X

X

X

Shinaku Inlet

X

X

X

Warmchuck Inlet

X

o

o

o

Tonowek Narrows

X

o

o

-

Tuxekan Passage

X

o

o

-

Sierra Sound

X

o

o

-

Shakan Pass (El

X

o

o

—

Capitan Pass)

Local names, exact locations unknown:

Sugar Point
Eleven Mile
Hornbrooke Island

x
x
x

Figure 6. — Chart of spawning beaches in the vicinity of Frederick Sound.

10

Table 3. --Spawning beaches in the vicinity of Frederick Sound
(x = spawning observed; o = no spawning observed;
- = not surveyed)

Aerial survey
Number Locality Rounsefell 1953 1954 1955

1

2

3

4

5

6

7

8

9
10
11
12
13
14
15
16
17
18
19
20

Ideal Cove

mm

o

X

Hicks Point

X

o

o

Little Duncan Bay

o

o

X

Duncan Canal

X

o

o

o

Point Baker

o

X

o

No Name Bay

o

X

X

Elena Bay

o

X

-

Rocky Pass Inlet

X

o

o

o

Port Camden

o

o

X

Saginaw Bay

X

o

-

Hamilton Bay

X

o

o

o

Kake

X

o

o

o

Cape Bendel

o

X

o

Farragut Bay

o

X

o

Port Houghton

X

o

o

o

Pybus Bay

X

o

X

o

Pleasant Bay

X

o

o

o

Mole Harbor

X

o

o

o

Flaw Point

o

X

o

Glass Peninsula west

X

X

o

shore

11

CONTINUATION
LYNN CANAL

^Eogle Hbr
| Pearl Hbr

Figure 7. — Chart of spawning beaches in the vicinity of Auke Bay.

12

Table 4. --Spawning beaches in the vicinity of Alike Bay

(x = spawning observed; o = no spawning observed;
- = not surveyed)

Aerial survey
Number Locality Rounsefell 1953 1954 1955

1

2

3

4

5

6

7

8

9
10
11
12
13
14
15
16
17
18

19
20
21
22
23

Idaho Inlet

X

-

o

-

Mud Bay

X

-

o

-

Flynn Cove

X

-

o

M

Port Frederick

X

-

o

-

Douglas Island

X

X

o

o

Spuhn Island

X

o

o

Coghlan Island

X

X

o

X

Auke Bay

X

X

X

X

Auke Cape

X

X

X

Point Louisa

X

X

X

X

Point Lena

X

X

X

X

Lena Cove

X

o

X

X

Point Stephens

X

o

o

X

Tee Karbor

X

X

X

X

Pearl Harbor

X

X

X

Eagle Harbor

X

X

X

Eagle River

o

X

X

Mainland east of Benj

amin

X

X

X

Island

Bridget Cove

X

X

X

Berners Bay (Echo Cove)

o

X

o

Flat Bay

-

X

X

Nudik Point

m

X

X

Tanani Point

-

o

X

13

Figure 8. — Chart of spawning beaches in the vicinity of Sitka.

14

Table 5. --Spawning beaches in the vicinity of Sitka

(x = spawning observed; o = no spawning observed;
- = not surveyed)

Aerial survey
Number Locale Rounsefell 1953 1954 1955

1

2

3

4

5

6

7

8

9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33

1/ Rounsefell reports spawning from Silver Bay to Whitestone Narrows.

Presumably this was not continuous and therefore may or may not include
the beaches utilized in recent years.

2 / Exact location unknown, presumably near Hood Bay.

Port Alexander

X

M

-

-

Redfish Bay

X

o

-

o

Biorka Island

X

o

o

o

Redoubt Bay

o

o

X

Kidney Cove

X

o

X

Ilput Island

o

o

X

Taigud Islands

X

X

X

Korga Island

X

X

X

Kizhuchia Creek

X

X

X

Caution Island

X

X

X

Povorotni Point

X

X

X

Mielkoi Cove

X

X

X

Three Entrance Bay

X

X

X

Cape Burunof

X

o

X

Pirate Cove

X

X

X

Samsing Cove

X

X

X

Sandy Cove

X

o

X

Deep Inlet

X

o

o

Aleutkina Bay

X

o

X

Leesoffskaia Bay

o

X

X

Silver Bay

1/
Jamestown Bay-
Whale Islandi'
Apple Island—'
Kasiana Island-r
Middle Island—
Starrigavan Bay—'

X

X

o
o

o

X

o
o

X

X

o

o

X

o

X

X

X

o

o

X

X

o

o

X

X

o

o

X

Whitestone Narrows

X

o

o

o

Kakul Narrows

o

X

o

Kelp Bay

o

X

-

Hood Bay

X

o

o

-

Killisnoo Lagoon

X

o

o

-

Kootznahoo Inlet ,

2/
Stretchers Cove—

X
X

o

o

-

15

listed by Rounsefell in 1930 show that 84
additional beaches have been located since
1953. However, spawning has not been
observed on 37 beaches listed by Rounsefell.
The large number of new spawnings discovered
is accredited to make extensive coverage
afforded by aerial surveys.

Each year the initial spawning in
Southeastern Alaska occurs in the vicinity
of Craig during late March. Kah Shakes,
Sitka, and Auke Bay spawnings follow and
are usually completed in early May. Spawn-
ing times in Behm Canal, Etolin Island, and
Frederick Sound are variable and have been
reported in late April, May, and early June.
Some areas do not conform to the northerly
and westerly progression in spawning time
described by Rounsefell (1930).

LITERATURE CITED

ROUNSEFELL, GEORGE A.

1930. Contribution to the biology of

the Pacific herring, Clupea pal-
lasii, and the condition of the
fishery in Alaska. Butlletin of
the U. S. Bureau of Fisheries,
vol. 46, pp. 225-320. Document
No. 1080.

TAYLOR, F. H. C.

1955. The Pacific herring (Clupea pal-
lasii) along the Pacific coast
of Canada. International North
Pacific Fisheries Commission,
pp. 105-128.

Considerable variation was noted in
physical characteristics of spawning beaches,
but ground surveys indicated that most eggs
were attached to eelgrass or rockweed.

16

INT.DUP.,D.C60- 49 812

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5 WHSE 01317

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